In response to the relatively small meteor which broke up near Chelyabinsk, Russia in February 2013 and ongoing investigation of Near Earth Object (NEO) close encounters with earth which could seriously impact life on earth, the U.S. Congress has issued a mandate to the National Aeronautics and Space Administration (NASA) to protect planet Earth. NASA has since issued a Grand Challenge to capture an asteroid, or remove a boulder on a larger asteroid, and return samples to earth in about 2025.
The United Nations also has an international task force to investigate an asteroid re-direct demonstration project, currently planned for 2023. Several businesses are planning to mine asteroids in space. To optimally mine the asteroids, the asteroids may need to be transferred to other locations in space such as the earth-moon Lagrange Point L1 or into an orbit around the moon.
Man-made space-object debris is an additional concern. An estimated 4.4 million pounds of space-object debris are in low-earth orbit. These space objects can be catastrophic for humans and spacecraft. The International Space Station dodges man-made space-object debris each year.
Expandable capture bag concepts to capture an asteroid or other space objects have been promoted by NASA and various private enterprises. While these prior art expandable bags can be stowed somewhat compactly and deployed to a larger size to contain a space object, they typically are constructed from non-expandable/non-stretchable textiles impregnated with an elastomer to form a pressure barrier to contain the pressurized gas.
Expandable/stretchable textile fibers are similar to a coiled spring. The fibers uncoil under tension, and then return to their coiled configuration when the tension is removed. Expandable/stretchable textiles are difficult to impregnate with an elastomer and still allow the textile to expand or stretch. When an elastomer is impregnated into an expandable textile, the elastomer prevents the textile fibers from uncoiling. The result is that the textile becomes essentially non-expandable and non-stretchable.
Prior art capture bag systems utilize non-stretchable pressurization (hose/tube) systems because the impregnated elastomer restricts the textiles' ability to stretch and expand. Consequently, the entire deployed length of the hose or tube must be stowed. The result is a system having a large stowed volume and a relatively high mass.
In addition, the prior art capture bag systems deploy to a large diameter and block sensors onboard the spacecraft used to identify and accurately locate a space object.
Accordingly, there is an as of yet unmet need in the art for a space-object capture apparatus that: 1) is made of components that may be compactly stowed at a size and length significantly less than when deployed; 2) is made of components having a lower combined mass than prior art systems; 3) maintains an adequate pressurized gas barrier without components constructed from non-expandable elastomer-impregnated materials; 4) is constructed using materials that are simultaneously expandable, stretchable, abrasion resistant, and impervious to ballistics; and, 5) upon deployment, continues to allow spacecraft sensors to operate and operators to view space from within the apparatus.